Identification of 5-HT2 Serotonin Receptor Modulators through the Synthesis of a Diverse, Tropane- and Quinuclidine-alkaloid-Inspired Compound Library.

The recombination of natural product (NP) fragments in unprecedented ways has emerged as an important strategy for bioactive compound discovery. In this context, we propose that privileged primary fragments predicted to be enriched in activity against a specific target class can be coupled to diverse secondary fragments to engineer selectivity among closely related targets. Here, we report the synthesis of an alkaloid-inspired compound library enriched in spirocyclic ring fusions, comprising 58 compounds from 12 tropane- or quinuclidine-containing scaffolds, all of which can be considered pseudo-NPs. The library displays excellent predicted drug-like properties including high Fsp3 content and Lipinski's rule-of-five compliance. Targeted screening against selected members of the serotonin and dopamine G protein-coupled receptor family led to the identification of several hits that displayed significant agonist or antagonist activity against 5-HT2A and/or 5-HT2C, and subsequent optimization of one of these delivered a lead dual 5-HT2B/C antagonist with a highly promising selectivity profile.

Highly efficient direct visible-light-mediated oxidative esterification of aldehydes.

A very efficient one-pot procedure for the direct oxidation of aldehydes to esters mediated by visible-light is presented. Utilizing a combination of indium triflate and N-bromosuccinimide, NBS, with either ortho-esters or alcohols provided rapid access to a variety of esters. Certain substrates convert fully within a few seconds, other more challenging tert-butyl esters were formed in good yield after no more than 4 h.